Tool for making electrical connections having insulation scraping means



Oct. 14, 1969 R. F. COBAUGH 3,471,916

TOOL FOR MAKING ELECTRICAL CONNECTIONS HAVING INSULATION SCRAPING MEANS Original Filed May 14, 1964 4 Sheets-Sheet 1 Oct. 14, 1969 R. F. COBAUGH 3,471,916

TOOL FOR MAKING ELECTRICAL CONNECTIONS HAVING INSULATION SCRAPING MEANS Original Filed May 14, 1964 4 Sheets-Sheet 2 Oct. 141, 1969 R. F. CQBAUGH 3,471,916

TOOL FOR MAKING ELECTRICAL CONNECTIONS HAVING INSULATION SCRAPING MEANS Original Filed May 14, 1964 4 Sheets-Sheet 5 Oct. '14, 1969 R. F. COBAUGH TOOL FOR MAKING ELECTRICAL CONNECTIONS HAVING INSULATION SCRAPING MEANS 4 Original Filed May 14, 1964 4 Sheets-Sheet 4.

nited States Patent 3,471,916 TUOL FOR MAKING ELECTRICAL CONNECTIONS HAVING INSULATION SCRAPING MEANS Robert Franklin Cobaugh, Hershey, Pa., assignor to AMP Incorporated, Harrisburg, Pa.

Original application May 14, 1364, Ser. No. 367,479, now Patent No. 3,330,022, dated July 11, 1967. Divided and this application May 24, 1967, Ser. No. 640,974

Int. Cl. H01r 3/00 US. Cl. 29-203 4 Claims ABSTRACT OF THE DISCLOSURE Tool for making clip-type electrical connections has mandrel and clip pusher. When connection is made, wire is dragged over mandrel and onto post by terminal clip which is pushed by clip pusher. Present invention comprises scraper in mandrel which bears against wire while it is being dragged over mandrel. Scraping of Wire results in removal of thin-film insulation and/or removal of oxides on wire surface.

This invention relates to electrical connections and to an improved method and apparatus for making electrical connections among a series of terminal posts. This application is a division of my copending application, Ser. No. 367,479, filed May 14, 1964, for Tool for Making Electrical Connections for a Series of Terminal Posts, now Patent No. 3,330,022, granted July 11, 1967.

My above-identified copending application discloses and claims a method and apparatus for forming electrical connections between terminal posts and conductors by means of open-sided terminal clips which are telescopically movable onto the posts. In accordance with the general principles of the invention disclosed and claimed in my copending application, the end of the conductor is positioned with its axis extending transversely of the axis of the terminal post and the terminal clip is moved over a suitable mandrel, against the conductor and onto the post in a manner such that the clip drags the conductor over the surface of the mandrel and onto the post. After the clip comes to rest on the post, the conductor is held against a surface of the post and emerges from confined relationship between the clip and the post at the end of the clip which is nearest to the base of the post. The present invention utilizes the general principles of the invention of application Ser.

No. 367,479, now Patent No. 3,330,022, and is particularly directed to the problem of connecting a single conductor serially to three or more terminal posts.

It is accordingly an object of the invention to provide an improved series connection for three or more terminal posts. A further object is to provide an improved method L of forming series connections for a plurality of terminal posts. It is a further object of the invention to provide an apparatus for connecting a single wire of indeterminate length to a plurality of terminal posts by means of a single terminal clip on each post with the wire extending from the first post to the last post of the series without being cut or otherwise interrupted.

These and oher objects of the invention are achieved in a preferred embodiment thereof in which the end portion of a wire extending from a substantially endless source is electrically connected to a first post in a series of posts by positioning a wire with its axis extending transversely of the axis of the post and moving an opensided terminal clip telescopically onto the post in a manner such that the clip drags the wire onto the post and holds it against the surface thereof. After this first connection has been made, the end of the wire will ice emerge from the end of the clip which is proximate to the base of the post. The wire will extend upwardly from the base of the post and emerge from confined relationship at the remote end of the clip and extend to the endless source. The wire is then, without being cut, positioned over the second and each subsequent post in the series and a terminal clip is moved past the wire and onto the second post and each subsequent post. After the second clip has been moved onto the second terminal post, the wire will extend from the remote end of the first terminal clip on the first terminal post to the proximate end of the clip on the second terminal post and will be confined against the second terminal post by this second clip. The wire will emerge from the remote end of the second terminal clip and extend to the proximate end of a clip on the third terminal post of the series. In this manner, any desired number of terminal posts can be electrically connected in series without cutting the wire. The present invention contemplates the usage of a clip applying tool comprising a mandrel adapted to support an individual terminal clip 'and means for moving a clip over the mandrel and onto a post. An opening extending transversely through the mandrel and transversely of the path of movement of the terminal clip is provided for the wire. The arrangement of the mandrel and the opening in the mandrel is such that an intermediate portion of the wire can be connected to an intermediate post of the series during usage as explained above.

In the drawing:

FIGURE 1 is a perspective view of a preferred form of hand tool for making electrical connections in accordance with the invention;

FIGURE 2 is a sectional side view of the frontal por- 3 tion of the hand tool of FIGURE 1 showing the positions of the parts at the beginning of an operating cycle;

FIGURE 3 is a view similar to FIGURE 2 but show ing the relative positions of the parts at a time midway through the operating cycle of the tool and immediately before a terminal clip is moved onto a terminal post;

FIGURE 4 is a view showing an electrical series connection among a series of terminal posts in accordance with the invention;

FIGURE 4a is a view similar to FIGURE 4 showing a series connection with wire having a relatively thick insulating sheath thereon;

FIGURE 5 is a view similar to FIGURE 2 but showing an alternative form of hand tool in accordance with the invention which is particularly adapted to form electrical connections with wire of the type having a relatively thick insulating sheath thereover;

FIGURE 6 is a view similar to FIGURE 5 but showing the positions of the parts at a time midway through the operating cycle of the tool of FIGURE 5;

FIGURE 7 is a fragmentary perspective View showing the clip pushing device of a hand tool of the type shown in FIGURES 2 and 5;

FIGURE 8 is a sectional view illustrating the manner in which the clip pusher moves over the mandrel of the tool of FIGURE 1 and illustrating the manner in which a strip of terminal clips is fed over the mandrel;

FIGURE 9 is a perspective fragmentary view showing the mandrel and the clip pusher of a further embodiment of the invention;

FIGURE 10 is a sectional plan view showing the mandrel and clip pusher of FIGURE 9 and illustrating the relative positions of the parts when the clip is being pushed over the mandrel; and

FIGURE 11 is a perspective view of a terminal clip of the type used to form electrical connection as shown in FIGURE 4.

A typical terminal clip 2 (FIGURE 11) for making an electrical connection in accordance with the principles of my copending application, Ser. No. 367,479fcomprises a web portion 4 having sidewalls 6 extending from its marginal edges, these sidewalls being reversely curled as shown at 8 towards each other and towards the underside of the web. A pair of ears 10 are struck up from the leading end of the clip and function as a strain relief and wire supporting means for the emergent wire as indicated in FIGURE 4. The internal surface of the web 4 is provided with transversely extending grooves which define spaced-apart ribs 13 as shown in FIGURE 2. After the clip has been applied to a post, the wire is confined between a surface of a rectangular post 14 and the internal surface of the web portion 4 of the clip and is held against and in electrical contact with the surface of the post as shown in FIGURE 4. The lower end 16 of the clip as viewed in FIGURE 4 is herein designated as the proximate end with reference to the panel 17 from which the terminal post 14 extends while the upper end 18 of the clip is designated at the remote end of the clip. FIGURE 4 shows a series connection among a plurality of terminal posts 14a, 14b, 14c, 14d in accordance with the principles of the present invention. The wire 12 in FIGURE 4 is provided with a thin film of insulating material, such as polyvinyl formal resin or other suitable polymeric material which is removed in the vicinity of each of the electrical connections in a manner described below.

FIGURES 1-3 show a manually actuated hand tool for forming an electrical connection in accordance with the present invention, this tool being in most respects similar to the hand tools disclosed and claimed in Patent No. 3,249,992 and Patent No. 3,186,073. The tool 20 comprises a sheet metal outer housing 22 and a sheet metal inner housing 24, these housing members having depending handle portions 26, 28 which form a pistol-type grip. A rectangular frame member (not shown) which is contained within the inner housing 24 has a channel-shaped projection 30 which extends beyond the forward end of the housing members 22, 24 and a block 32 is contained between and secured to the depending sidewalls of the extension 30. A clip pusher (FIGURE 7) 34 is slidably mounted relative to the frame extension 30 and comprises an upper side 36 which is disposed against the underside of the extension 30 and depending sidewalls 38. These sidewalls have inwardly directed flanges 40 at their lower end so that a strip of end-to-end connected terminal clips 2 can be contained within the clip pusher with the curled edges of the clips resting on the flanges of the sidewalls as shown in FIGURE 8.

At the beginning of an operating cycle, the parts will be in the relative positions of FIGURE 2 with the leading clip 2' of the strip disposed in the leading end portion of the clip pusher and with the trailing side of this leading clip engaged by the inwardly turned ends 42 of a pair of arms 41. These arms 41 are integral with, and extend from, a yoke member 43 mounted in a recess of the clip pusher as described more fully in the above-identified application, now Patent No. 3,186,073. For purposes of the instant disclosure, it is suflicient to say that upon leftward movement of the clip pusher from the position of FIGURE 2, these inwardly turned end portions 42 of the arms 41 push the entire strip of clips leftwardly by virtue of their engagement with the trailing end of the leading clip 2' of the strip. As described more fully below, this leading clip 2' is severed from the strip of clips during the leftward movement of the clip pusher 34.

A mandrel block generally indicated at 46 is clamped by means of a fastener 48 between a pair of spaced-apart side extensions 44 of the block 32. A generally T-shaped mandrel is provided on the upper surface of the mandrel block 46, this mandrel comprising a rib portion 52 and a head portion 50 (see FIGURE 8), the width of the head being slightly less than the distance between the opposed internal surfaces of the sidewalls 6 of the individual terminal clips so that the leading clip can be moved from the position of FIGURE 2 relatively leftwardly over the mandrel and subsequently onto a terminal post. An opening 54 extends through the head and rib portions of the mandrel, and rearwardly through the mandrel block. This opening is in alignment with an opening 55 in the block 32 and has a diameter sufiicient to permit relative movement therethrough of the wire 12 as shown in FIG- URE 2. Advantageously, a relatively shallow groove 56 is provided on the upper surface of the head 50 and slopes upwardly from the upper end of the opening 54 to the upper surface of the mandrel head. The mandrel head 50 extends rearwardly of the tool beyond the opening 54 as indicated at 58 so that the leading clip 2' of the strip overlaps this extension of the mandrel head.

As previously mentioned, the leading clip 2 of the strip must be severed from the strip of clips during initial leftward movement of the clip pusher 34 from the position of FIGURE 2. This is accomplished by means of a pair of stops 60, 62, the leading stop 60 being disposed in a blind hole in the block 32 and being upwardly biased by means of a coil spring 61. The trailing stop 62 extends through an oversized opening 70 in a pivoted lever 64 and is also received in a hole in the block 32. This trailing stop is upwardly biased by a coil spring 63. The lever 64 is contained in an elongated channel or slot 66 in the block 32 and is pivoted to the block intermediate its ends as shown at 68. The stops 60, 62 have projections 74, 76 on their upper ends which extend into the path followed by the strip of clips during relative leftward movement from the position of FIGURE 2. The projection 74 on the stop 69 has a rightwardly facing surface as viewed in FIGURE 2 which normally bears against the leading end of the leading clip 2' while the trailing stop 62 has a rightwardly facing sloping surface which normally bears against the next adjacent clip of the strip. It will be apparent that this trailing stop 62 can thus be biased downwardly against the force of the spring 63 upon relative leftward movement of the strip of clips. By virtue of the oversized opening 70 in which the trailing stop 62 is diposed, this stop is independent of the lever 64. The forward stop 60 is connected to the left-hand end of the lever 64 as shown at 72 so that upon counterclockwise swinging of the lever about its pivotal axis 68 this leading stop is lowered as explained below.

Lever 64 has a depending arm on its right-hand side as viewed in FIGURE 2 with a sloping cam surface 81 at its lower end. This cam surface is engaged by a pin 78 which extends between the sides of the forward end of the outer housing 22 so that upon relative leftward movement of the pin 78 with respect to the surface 81 the lever 64 is swung through a slight arc in a counterclockwise direction thereby to lower the leading stop 60 and to permit the leading clip 2 to move past the projection 74 on the leading stop. The stop 60, however, is biased by the spring 61 against the underside of the leading clip 2' and moves upwardly against the leading end of the next adjacent clip after the leading clip has passed the stop 74. Such upward movement of the projection 74 is permitted since the pin 78 will have passed the depending arm 80 of the lever by the time the leading clip moves past the projection 74.

As previously mentioned, the tool of FIGURE 1 is particularly adapted to form series connections among several terminal posts with wire 12 having a thin adherent film of polymeric material thereon, such wires commonly being denominated as magnet wires and being used for coil windings or the like. In order to remove a portion of this adherent film, a scraper 82 is provided in the mandrel adjacent to the forward end thereof. This scraper is mounted in an opening extending through the mandrel head portion 50 and has a sloping side 84 which faces the wire when the parts are in the positions of FIGURE 2. An enlarged lower end 86 of the scraper 82 is contained within a counterbored opening in the mandrel in which a spring 88 is contained for biasing the scraping tool upwardly. It will be apparent that the edge of this tool will be pressed against the underside of the wire during relative movement of the wire thereover. It should be added that the ribs 11 on the internal surface of the web of the clip are pressed into the Wire while the clip moves over the mandrel and tend to lock the clip to the wire thereby preventing relative movement of the wire with respect to the clip while the clip is being dragged over the edge of the scraping tool. Further details of this feature of the tool of FIGURE 1 are set forth in Patent No. 3,275,968. The wire is supplied from a substantially endless source comprising a spool 90 mounted on a pin 92 extending from the outer housing member 22 at the rearward end thereof.

In use and when a connection is being made with a first post 14a of a series, the parts will be in a relative position of FIGURE 2 with the end portion of wire 12 threaded through the openings 54, 55 and intersecting the path of movement of the leading terminal clip. The operator first squeezes the handles 26, 23 to bring about relative movement of the clip pusher 34 from the position of FIGURE 2 to the position of FIGURE 3. During this movement of the clip pusher, the leading stop 60 will be depressed as explained above, to permit leftward movement of the leading clip 2' and this leading stop will move against the leading end of the next adjacent clip when it comes into alignment with the projection 74. During the final portion of this initial leftward stroke of the clip pusher, the leading clip will be broken away from the strip of clips as explained in more detail in Patent No. 3,249,992.

The leading clip then moves against the upwardly projecting end portion of the wire 12 and drags this portion of the wire over the upper surface of the head 50 of the mandrel, through the groove 56, and across the upwardly biased edge of the scraping tool 82 thereby to scrape away a portion of the insulating film on the underside of the wire. The transversely extending ribs on the underside of the web function to prevent relative movement between the wire and clip as explained above. After the handles have been fully moved together, the clip pusher will be in the position of FIGURE 3 with the leading clip 2' broken away from a strip and with a portion of the wire clamped against the upper surface of the mandrel head adjacent to the end thereof. The operator then positions the tool in alignment with the terminal post 14a with the upper end of this post disposed against the shoulder formed by the end 51 of the mandrel head. The operator then pushes the tool relatively against the post to bring about the further relative movement of the clip pusher with respect to the mandrel, the block 32 and the other parts of the tool as explained in Patent No. 3,249,992. During such movement of the clip pusher, the leading clip 2' is moved relatively downwardly over the post 14a to the position shown in FIGURE 4. The operator then pulls an amount of wire from the spool 90 through the aligned openings 55, 54 which is sutficient to reach to the second post 14b and repeats the steps outlined above for moving a second clip onto the post 14b and establishing the electrical connection with the second post. The same steps are repeated for the posts 140 and 14d to produce the series connection between these four posts as indicated in FIGURE 4. During movement of each clip over the mandrel, a portion of the wire is pressed against the edge of the scraping tool 82 by the clip and a short length of wire is stripped of the film of insulation so that the remaining portion of the wire which extends between the posts retains its insulating film.

In the finished electrical connection, the end portion of the wire 14 enters confined relationship between the clip 2 and the post 14a at the proximate end 16 of the clip and emerges from confined relationship at the remote end 18 of the clip. In each subsequent electrical connection of the series, the intermediate portion of the wire enters confined relationship at the proximate end of the post and similarly emerges from confined relationship at the remote end of the post. In the last connection of the series, at post 14d, the end portion of the wire emerges from confined relationship at the remote end 18 of the clip which is telescoped onto the post 14d.

A salient advantage of the invention is that each post 14a-14d of the series of posts to be connected is con nected to the same length of wire with the insulation stripped from the wire only in the immediate areas of electrical contact with the several posts. The electrical connections with the posts 14b, thus constitute tap connections with the through wire 12. From the standpoint of the quality of electrical connections made with the several posts, the invention thus permits the achievement of the series connection with a reduced number of interfaces as compared with previously known connecting methods; in other words, the single length of wire which connects the several posts of the series in FIGURE 4 extends uninterruptedly from the posts 14a to 14d with only two individual interfaces separating, from an electrical standpoint, the post 14a from any other one of the posts in the series.

From a standpoint of the mechanical aspects of making the electrical connections of FIGURE 4 and the manipulative steps required to make these connections, it is apparent that the invention reduces substantially the number of clips required for this group of series connections in that only one terminal clip is required on each of the terminal posts 14a-14d even though the intermediate posts 14b, 14c, are each connected to two adjacent terminal posts in the series; for example, the post 14b is connected to the post 14c and the post 14a. The manipulative steps are also substantially reduced in that it is only necessary to go through the cycle of operating the tool once for each of the posts 14a-14d.

The principles of the invention are not limited to usage in instances where film insulated wires of the type disclosed in the embodiment of FIGURE 1 are involved. If it is desired to make a series of electrical connections among terminal posts with wire having the more conventional relatively thick insulating sheath such as a vinyl sheath thereon, an embodiment of the invention of the type shown in FIGURES 5 and 6 can be employed. In these figures, the wire 94 has a relatively thick insulating sheath thereover which is removed at suitable intervals to expose the metallic core of the wire. The tool shown in FIGURES 5 and 6 is substantially similar to the tool of FIGURES 1-3 so that a detailed description of this modified form of tool in accordance with the invention is not deemed to be necessary. Accordingly, the various parts of the tool of FIGURE 5 are identified with the same reference numerals, diflerentiated by prime marks, as those used to describe the embodiment of FIGURE 1. The tool of FIGURE 5 differs from the tool of FIG- URES 1-3 in that the openings 54', 55' are of a diameter sufficiently large to receive the insulated portion 94 of the wire. The tool of FIGURE 5 also difiers from the embodiment of FIGURE 1 in that the scraping tool 82 is not provided in the mandrel block 46' since it is not necessary to scrape wire of this type. The operation of the tool of FIGURES 5 and 6 is substantially similar to the operation of the previously described embodiment in that the leading clip 2 is pushed against a stripped portion 96 of the wire and drags this stripped portion over the mandrel to the position of FIGURE 6. The tool is then pgsitioned against the end of a terminal post and pressed axially towards the post to cause further relative movement of the clip pusher 34' whereby the leading clip is moved onto the post and clamps the stripped portion of the wire against a surface of the post as described before.

It is advantageous to use a terminal clip 2 having an insulation supporting car 10 at each end when a series connection of the type shown in FIGURE 4a among a plurality of posts is being made with wire having a relatively thick insulating sheath. The provision of an car at each end of the clip provides for insulation supporting and strain relief means wherever the wire enters or leaves a terminal clip as disclosed in Patent No. 3,243,757.

FIGURES 9 and 10 show a further embodiment of the invention which is particularly intended for wire having a relatively thick insulating sheath thereover. The mandrel block 46 in this instance has a slot 54" opening into the side of the mandrel into which the insulated wire is placed, this slot 54 serving substantially the same function as the opening 54 of the embodiment of FIG- URE 1, that is, to receive the intermediate portion of the wire which is to be connected to the post.

The clip pusher 34" has an enlarged end 98 in which the leading clip is nested while it is being pushed over the mandrel, past the wire and onto the post. It should be explained that the strip of clips is not fed axially within the clip pusher in the embodiment of FIGURES 9 and 10 but, are rather transferred laterally from beneath the clip pusher into a position in alignment with the path of reciprocation of the clip pusher. Tools of this general type are disclosed in Patent No. 3,186,072.

Rearwardly of the enlarged end 98 of the clip pusher, the sidewall 100 of the clip pusher is cut away as shown at 102 and the underside of the top wall is cut away to form a surface 104 which entends diagonally from the side 100 to the side 106 and towards the front 98 of the clip pusher. In use, the stripped portion of the wire is disposed in the slot 54" of the mandrel and the clip pusher is actuated to drive a clip leftwardly in FIGURE 9 over the mandrel, against the wire, beyond the mandrel and onto a post. During such movement of the clip pusher, the leading end of the clip engages the stripped portion of the wire and drags the stripped portion through the groove 56" and over the surafce of the head of the mandrel. The next adjacent insulated section of the wire is pulled through the slot 54" against the underside of the clip pusher and is pushed rightwardly in FIGURE 9 by the surface 104 so that the wire is ejected from the channel 54". The clip pusher can then push the clip beyond the mandrel and onto the terminal post and the immediately adjacent insulated section of the wire will trail the clip on the right-hand side thereof as viewed in FIG- URE 9.

The embodiment of FIGURE 9 is particularly advantageous where the insulating sheath on the wire is relatively thick and where it is impractical to provide a sufficiently large opening 54' in the embodiment of FIGURE 3 to accommodate the wire.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing fi'om the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only. The actual scope of the inven- 0 tion is intended to be defined in the following claims when viewed in their proper perspective against the prior art.

What is claimed is:

1. In a device for electrically connecting a conductor to a terminal post by means of a terminal clip, said clip having a web portion and having an axially extending open seam on the side thereof which is opposite to said web portion, said clip being telescopically movable onto said post, said device comprising a mandrel conforming to the internal cross-section of said clip, and clip moving means for moving said mandrel along a predetermined path extending over, and beyond one end of, said mandrel whereby, upon aligning said device with a terminal post and actuating said clip moving means to move a clip along over said mandrel past a transversely extending conductor and onto said post, said conductor is dragged over said mandrel and onto said post, the improvement to said device comprising: scraping means on said mandrel for Scraping insulation from said conductor, said scraping means extending transversely across said mandrel whereby the side of said conductor which is dragged over said mandrel is scraped during movement over said mandrel, and said side is thereafer dragged onto said post and held against, and in electrical contact with, said post.

2. A device as set forth in claim 1 wherein said scraping means comprises a scraping knife mounted in said mandrel and having a scraping edge extending transversely across said mandrel.

3. A device as set forth in claim 1 wherein said scraping means comprises a block in said mandrel, said block being resiliently biased into intersecting relationship with said path whereby said block is resiliently biased against said conductor during movement of said conductor over said mandrel.

4. A device as set forth in claim 1 wherein said scraping means comprises a block in said mandrel, said block being resiliently biased into intersecting relationship with said path, a scraping edge on said block extending transversely of said path whereby, said edge is resiliently biased against said conductor during movement of said conductor over said wire.

References Cited UNITED STATES PATENTS 3,186,072 6/1965 Cobaugh. 3,186,073 6/1965 Cobaugh et al. 3,243,757 3/1966 Cobaugh 33997 3,249,992 5/ 1966 Long. 3,330,022 7/ 1967 Cobaugh.

THOMAS H. EAGER, Primary Examiner U.S Cl. X.R. 

